<template>
  <div class="box">
    <h2>Event2组件</h2>
    <button @click="$emit('click',3)">增加3</button>
    &nbsp;&nbsp;
    <button @click="$emit('minus',5)">减少1</button>
    &nbsp;&nbsp;
    <button @click="$emit('ride',2)">乘以2</button>
  </div>
</template>
